Seoul will send a formal proposal across the border tomorrow, he said, without elaborating on when the talks would be held.

The Kaesong complex, built in 2004 as a rare symbol of cooperation, had survived previous inter-Korean crises but eventually became the most high-profile casualty of two months of elevated tensions following a nuclear test by the North in February which sparked international condemnation.

Production at the estate, 10 kilometres over the border, has been suspended since North Korea withdrew its 53,000 workers from the zone in April at the height of soaring military tensions with the South.

Ryoo reiterated that the South wants the North to accept responsibility for what Seoul insists was the unilateral closure of Kaesong by Pyongyang, and give a written guarantee that it will never happen again.
"We want a clear answer from the North on preventing a recurrence," he said. "Otherwise, we will be left with no choice but to make a grave decision to prevent even bigger damages on our companies in the future," he said.
The North has said it was not responsible for the shutdown, arguing that its hand was forced by hostile South Korean actions and intimidation -- in particular, a series of joint military exercises with the United States. However, in an apparent gesture to lure Pyongyang to a fresh round of negotiations, Ryoo said Seoul would approve tomorrow five shipments of humanitarian aid for the North worth USD 1.25 million.